This invention relates to motorized vehicles and more particularly to instrumentation for detecting and indicating undesirable operating conditions in the engine or other vehicle components
In motorized vehicles of virtually all kinds, instruments are employed to alert the operator to any of various undesirable operating conditions such as overheating of the engine, low oil pressure and the like. In some vehicles similar instruments may be provided to indicate operating faults in components distinct from the engine. In earthmoving vehicles for example, where the engine operates a pump to supply pressurized fluid to hydraulic cylinders for manipulating elements of the vehicle, instruments may be present to indicate a low level of hydraulic fluid in the supply reservoir.
Heretofore, most instruments of this kind have simply detected the undesired condition and then signalled the operator by means of dial indicators, indicator lamps or audible means. The efficiency of these systems is greatly dependent upon the operator's careful attention to all of the several indicators and upon his judgment as to which may call for immediate correction and which may be deferred. In the latter case, where it is possible to continue operations in the presence of the fault, it is necessary that the operator remember the problem and arrange for maintenance at the conclusion of vehicle operation. As operators must be concerned with many other aspects of vehicle operation besides instrument observation and since vehicle operation may continue over extended periods of time, errors frequently occur from failure to observe a warning indicator or failure to make the right judgment about the need for corrective actions or from failure to remember a temporarily observed indication of some undesirable operating condition.